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991.
JianJun He ShiWei Xu ShaoBo Ma Jun Hu LiYong Zhang ChangBo Fu NingTao Zhang Gang Lian Jun Su YunJu Li ShengQuan Yan YangPing Shen SuQing Hou BaoLu Jia Tao Zhang XiaoPeng Zhang Bing Guo Shigeru Kubono WeiPing Liu 《中国科学:物理学 力学 天文学(英文版)》2016,59(5):652001
In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ~(19)F( p,α)~(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions. 相似文献
992.
We show that by placing a metal plate next to a two-dimensional phononic crystal, acoustic waves can tunnel through the combined structure at a specific frequency that lies inside the band gap of the phononic crystal. The enhanced transmission is attributed to the coupling of the input waves with the acoustically resonant states created between the metal plate and the phononic crystal. Experiments are in excellent agreement with the theoretical predictions. 相似文献
993.
Does the HyperCP evidence for the decay Sigma+ -->pmu+mu- indicate a light pseudoscalar Higgs boson?
The HyperCP Collaboration has observed three events for the decay Sigma+ -->p mu+mu- which may be interpreted as a new particle of mass 214.3 MeV. However, existing data from kaon and B-meson decays provide stringent constraints on the construction of models that support this interpretation. In this Letter we show that the "HyperCP particle" can be identified with the light pseudoscalar Higgs boson in the next-to-minimal supersymmetric standard model, the A10. In this model there are regions of parameter space where the A10 can satisfy all the existing constraints from kaon and B-meson decays and mediate Sigma+ -->p mu+mu- at a level consistent with the HyperCP observation. 相似文献
994.
By employing the self-modulation birefringence difference in a semiconductor optical amplifier (SOA), an improved method is proposed to generate a complete optical single-sideband (OSSB) signal. Over 30 dB sideband suppression ratios (SSRs) of lower OSSB signals are obtained over a 12 dB input power range and a 36 nm wavelength span, with a maximum of over 35 dB. Upper OSSB signals with an SSR of over 15 dB are observed using a SOA for what is believed to be the first time. This method is effective even for the carrier-suppressed signal. The theory for OSSB generation in an SOA is extended and verified by experiment. 相似文献
995.
Some photonic crystals (PCs) consisting of complex lattices of dielectric cylinders can have an effective refraction index (neff) of −1. Subwavelength imaging by a slab of a honeycomb PC of dielectric cylinders with neff=−1 is investigated and an open resonator with a quality factor higher than 3000 is designed with the same PC. Air–PC interfaces with low reflection are also used for the slab lens and open resonator. 相似文献
996.
Jingsong He Kelei Tian Angela Foerster Wen-Xiu Ma 《Letters in Mathematical Physics》2007,81(2):119-134
Based on the Orlov and Shulman’s M operator, the additional symmetries and the string equation of the CKP hierarchy are established, and then the higher order
constraints on L
l
are obtained. In addition, the generating function and some properties are also given. In particular, the additional symmetry
flows form a new infinite dimensional algebra , which is a subalgebra of W
1+∞.
相似文献
997.
We have performed first-principles calculations using full-potential augmented-plane-wave method to investigate the fundamental properties of the Cd1–xZnxTe alloys. The composition dependence of the lattice constant and the bulk modulus have been estimated from total energy calculations. By means of the analytical fitting the band structures in the vicinity of the Brillouin center a complete set of effective electron- and hole-masses have also been derived. In order to further understand the effects of the chemical bonding on the above macroscopic properties we then studied the relaxation behaviors and the changes of the electronic states upon alloying for x=0.25 system. The results presented here yield a general understanding of the fundamental properties for the Cd1–xZnxTe crystals studies. 相似文献
998.
"利用由无乳化剂的乳液聚合法和水浮法联用技术合成得到的有序排列的聚甲基丙烯酸甲酯(PMMA)微球为硬模板,以硝酸镁为镁源,并采用硝酸镁-柠檬酸-乙醇混合溶液浸渍PMMA微球后经干燥以及先后在300 ℃恒温灼烧3 h和500 ℃恒温灼烧5 h,制备出具有有序纳米孔道结构的MgO粒子.应用X射线衍射、高分辨扫描电子显微镜、透射电子显微镜/选区电子衍射以及N2吸附-脱附法等技术表征了PMMA和MgO样品的物理化学性质.结果表明,所得PMMA微球颗粒较为均匀,粒径约为284 nm,且排列规整有序.由PMMA硬模板 相似文献
999.
Jienan Li Lin Lin Bowei Jiang Chudong Wang Moutanou Modeste Judes Zeye Dan Wen Wei He Weifeng Qu Ying Liu Lagabaiyila Zha 《Electrophoresis》2021,42(9-10):1143-1152
DNA genotyping from trace and highly degraded biological samples is one of the most significant challenges of forensic DNA identification. There is a lack of simple and effective methods for genotyping highly degraded samples. In this study, a multiple loci insertion/deletion polymorphisms (Multi-InDels) panel was designed for detecting 18 autosomal Multi-InDels through capillary electrophoresis (CE) with amplicon sizes no longer than 125 bp. Studies of sensitivity, degradation, and species specificity were performed and a population study was carried out using 192 samples from Han populations in Hunan province in the south of China. The combined random match probability (CMP) of these 18 Multi-InDels was 3.23 × 10–12 and the cumulative probability of exclusion (CPE) was 0.9989, suggesting this panel could be used independently for human identification and could provide efficient supporting information for parentage testing. Complete profiles were obtained from as low as 62.5 pg of total input DNA after increasing the number of PCR cycles. Moreover, all alleles were detected from artificially highly degraded DNA after 80 min of boiling water bath treatment. This 18 Multi-InDels panel is simple, fast, and effective for the forensic analysis of highly degraded DNA. 相似文献
1000.
近年来, 过渡金属硫族化合物(TMDs)作为一种新兴的二维材料, 因其独特的层状结构及电学特性成为超级电容器电极材料的理想候选者之一. 本文介绍了二维TMDs的常用合成方法, 阐述了钼基、 钨基和钒基等TMDs在超级电容器中的研究进展, 分析了形貌、 尺寸和改性方法等因素对TMDs材料电化学性能的影响, 并对TMDs在超级电容器领域的工业化应用和挑战进行了总结与展望. 相似文献